US3706570A - Spectrally sensitized negative emulsion containing silver halide grains of less than 0.18 micron - Google Patents

Spectrally sensitized negative emulsion containing silver halide grains of less than 0.18 micron Download PDF

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Publication number
US3706570A
US3706570A US38485A US3706570DA US3706570A US 3706570 A US3706570 A US 3706570A US 38485 A US38485 A US 38485A US 3706570D A US3706570D A US 3706570DA US 3706570 A US3706570 A US 3706570A
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United States
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group
silver halide
agbri
alkyl group
emulsion
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Expired - Lifetime
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US38485A
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Yoshiyuki Nakazawa
Tohru Sueyoshi
Akira Sato
Yashiharu Nakamura
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Fujifilm Holdings Corp
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Fuji Photo Film Co Ltd
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    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C1/00—Photosensitive materials
    • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
    • G03C1/06—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein with non-macromolecular additives
    • G03C1/08—Sensitivity-increasing substances
    • G03C1/10—Organic substances
    • G03C1/12—Methine and polymethine dyes

Definitions

  • the present invention relates to a silver halide spectrally sensitized photographic emulsion, and in particular to a fine-grain silver halide photographic emulsion of a type whose light sensitivity in the specific absorption wave length region of the silver halide is remarkably increased when the silver halide emulsion is subjected to a spectral sensitization by using a specific sensitizing dye.
  • sensitization by a sensitizing dye. Therefore, the selection of sensitizing dyes showing less of such a desensitizing action is desired for producing silver halide photographic light sensitive materials.
  • the grain size of the silver halide crystals in the silver halide emulsion be as small as possible, which results in, however, a decrease in the sensitivity thereof.
  • the present inventors have discovered that when a silver halide emulsion containing silver halide crystals having a mean grain size of smaller than 0.18 micron, or at least of which are smaller than 0.2 micron, is subjected to a spectral sensitization using a specific sensitizing dye by a conventional method, the photosensitivity in the specific absorption wave length region of the silver halide is remarkably increased and, in addition, the light sensitive Wave length region is enlarged.
  • a Capri Blue effect another well-known phenomenon is an increase in light sensitivity in the spectral absorption wave length region of a silver halide caused by a sensitizing dye. This efiect is due to an intense exposure over a short period of time of a silver halide emulsion when a desensitizing dye or a sensitizing dye is incorporated into the emulsion which has not been subjected to a sulfur sensitization or a reduction sensitization.
  • the elfect discovered by the inventors of the present invention is extremely difierent from the Capri Blue eflFect in that even if the silver halide emulsion containing silver halide crystals having the above-mentioned grain size has been subjected to a sulfur sensitization, a reduction sensitization, or a gold sensitization, the light sensitivity in the specific absorption wave length region of the silver halide is further greatly increased when the silver halide emulsion is spectrally sensitized by a specific sensitizing dye.
  • an object of the present invention is to provide a silver halide photographic emulsion having an enlarged spectral absorption wave length region and an increased light sensitivity in the specific absorption wave length region of silver halide by applying to the fine grain silver halide emulsion a spectral sensitization.
  • the present invention provides a silver halide photographic light-sensitive emulsion wherein the silver halide crystals have a mean grain size of less than 0.18 micron, or wherein at least 95% of the crystals have a mean grain size of less than 0.2 micron, and wherein at least one of the sensitizing dyes represented by the following formulae are incorporated in such an emulsion in an amount of from 1 to mg. per 1 kg. of the emulsion.
  • the above object of the present invention can be achieved by incorporating at least one of the sensitizing dyes represented by the following general Formulae I, II, III, IV, and V in a silver halide emulsion containing silver halide crystals having a mean grain size of smaller than 0.18 micron, or at least 95% of which are smaller than 0.2 micron in diameter.
  • Formula (I) wherein Z and Z each represents an oxygen atom, a sulfur atom, a selenium atom, NR N--R CH CH, or R and R each represents an alkyl group having 1-4 carbon atoms (such as a methyl group, an ethyl group, etc.), a substituted lower alkyl group (such as a fl-hydroxyethyl group, a fl-methoxyethyl group, a 'y-acetoxypropyl group, a fl-carboxyethyl group, a 'y-sulfopropyl group, etc.), an aryl group (such as a phenyl group), or an allyl group; R and R which may be mutually bonded through a polymethylene chain to form a ring, each represents an alkyl group having 14 carbon atoms, a substituted lower alkyl group (such as ,B-phenylethyl group, etc.), an
  • each of V, V W and W is a hydrogen atom or at least one of them is a phenyl group or a carboxyl group.
  • V W and W is a hydrogen atom or at least one of them is a halogen atom, an alkyl group having 1-4 carbon atoms,
  • V, V W and W are a sulfur atom or a selenium atom
  • at least one of V, V W and W is an alkoxyl group, a phenyl group a hydroxyl group, or a halogen atom.
  • each of V, V W and W is a hyrogen atom or at least one ofthem is an alkyl group having 1-4 carbon atoms, an alkoxyl group, a hydroxyl group, a dimethylamino group, or a halogen atom.
  • V W and W is a hydrogen atom or at least one of them is a halogen atom, an alkyl group havirig 1-4 carbon atoms, an alkoxyl group, a hydroxyl group, a phenyl group, or a dimethylamino group.
  • R and R of Formula I each represents an alkyl group having l-4 carbon atoms, a substituted lower alkyl group (such as a li-hydroxyethyl group, a fi-carboxypropyl group of a -sulfopropyl group), or an allyl group.
  • L L and L each represents CH or CR m, wherein R represents a hydrogen atom, an alkyl group having 1-4 carbon atoms, an aryl group (such as a phenyl group), or a substituted aryl group (such as an o-carboxyphenyl group, a p-hydroxyphenyl group, etc.); and wherein L or L may be bonded to R or R respectively, through a polymethylene chain; and wherein L and L or L and L may be bonded together through a polymethylene chain; and wherein V and V or W and W may form a benzene ring.
  • X represents an anion (such as the ions: halogen, perchlorate, thiocyanate, p-toluene sulfate, benzenesulfate, ethylsulfate, methylsulfate, etc.); and n is 0 or 1 (when n is 0, the formula forms an intermolecular salt).
  • R and R each represents an alkyl group having l-4 carbon atoms, or a substituted lower alkyl group (such as a fi-hydroxy ethyl group, a B-methoxy ethyl group, a 'y-acetoxypropyl group, a fl-carboxyethyl group, a 'y-sulfopro-pyl group, etc.); R and R which may be bonded to each other through a polymethylene chain, each represents an alkyl group having 14 carbon atoms, a substituted lower alkyl group (such as a fi-phenylethyl group, etc.), an aryl group (such as a phenyl group) or an allyl group; all of the substituents V V W and W are a hydrogen atom or at least one of them is an alkyl group having 1-4 carbon atoms, an alkoxyl group, a hydroxyl group, a phenyl group
  • Z represents an atomic group necessary to complete a S-membered or 6-membered heterocyclic ring such as a nucleus of the benzoxazole series (e.g., benzoxazole, S-chlorobenzoxazole, S-bromobenzoxazole, S-methylbenzoxazole, S-ethylbenzoxazole, S-methoxybenzoxazole, S-ethoxybenzoxazole, S-acetaminobenzoxazole, S-phenylbenzoxazole, 6-chlor0benz0xazole, 7-chlorobenzoxazole, etc.), a nucleus of the benzothiazole series (e.g., benzothiazole, 4-chlorobenzothiazole, 7-chlorobenzothiazole, S-chlorobenzothiazole, 4-phenylbenzothiazole, 4-methoxybenzothiazole, 4-methylbenzothiazo
  • R represents an alkyl group having 1-4 carbon atoms, a substituted lower alkyl group (such as a ,B-hydroxyethyl group, a 'y-sulfopropyl group, a 3- carboxyethyl group, etc.) or an allyl group
  • L represents CH, CH or CR wherein R represents a substituted lower alkyl group (such as a fi-carboxyethyl group, a 'yhydroxypropyl group, etc.), or a substituted aryl group (such as an o-carboxyphenyl group, a p-hydroxyphenyl group, etc.); R and L may be bonded to each other through a polymethylene chain, wherein L represents the L nearest to the heterocyclic ring containing Z and m is 1 or 2.
  • R R and R each represents a lower alkyl group, or a substituted lower alkyl group (such as a B-hydroxyethyi group, a fi-ca-rboxyethyl group, a y-sulfopropyl group, etc.);
  • L L and L each represents CH or CR R represents a lower alkyl group, an alkoxyl group (such as a methoxy group, etc.), an aryl group (such as a phenyl group), or a substituted aryl group (such as a o-carboxyphenyl group, a p-hydroxyphenyl group, etc.);
  • R represents a lower alkyl group, a substituted lower alkyl group (such as a B-hydroxyethyl group, etc.), an ary
  • the aforesaid effect is particularly remarkable with respect to gelatino silver halide photographic emulsions, but is also effective on other silver halide photographic emulsions employing other hydrophilic colloids than, gelatin, such as agar agar, collodion, water-soluble cellulose derivatives, polyvinyl alcohol, or other synthetic or natural hydrophilic resins.
  • the silver halide used in the silver halide photographic emulsion of this invention may be silver chloride, silver chlorobromide or silver iodobromide, but the use of silver chlorobromide or silver iodobromide is most preferable.
  • the sensitizing effect on the specific absorption wave length region of silver halide in the present invention largely depends on the grain size of the silver halide crystals. That is, in silver halide photographic emulsions having the same silver halide composition, the effect of the sensitizing dye on such silver halide emulsions is varied according to the grain size of the silver halide crystals incorporated in the emulsion, and if a photographic emulsion containing silver halide crystals having a mean grain size of larger than 0.18 micron in diameter is employed, the sensitizing dyes mentioned above show no sensitizing effect in the specific absorption wave length region of the silver halide.
  • the sensitizing ratio shown in the above table is a ratio of the sensitivity of a silver halide photographic emulsion, containing the sensitizing dye of the present invention, to the sensitivity, which is assumed to be 1, of a silver halide photographic emulsion containing no sensitizing dye.
  • At least one of the above-mentioned sensitizing dyes may be incorporated by a conventional method in a silver halide photographic emulsion chemically sensitized by an unstable sulfur compound and a gold complex salt.
  • the sensitizing dye is usually added to the silver halide emulsion as a solution thereof in a proper solvent such as methanol or ethanol.
  • the proportion of the sensitizing dye to be incorporated in the silver halide emulsion may be varied over the wide range of 1-150 mg. per one kg. of the emulsion according to the desired sensitizing effect.
  • the silver halide photographic emulsion of the present invention may be further subjected to a super-sensitization and a hyper-sensitization.
  • the silver halide photographic emulsion of the present invention may further be incorporated ordinary additives such as other chemical sensitizing dyes, a stabilizer, an anti-foggant, a color toning agent, a hardening agent, a surface active agent, a plasticizer, a developing accelerator, a color coupler and a fluorescent brightening agent, by conventional means.
  • ordinary additives such as other chemical sensitizing dyes, a stabilizer, an anti-foggant, a color toning agent, a hardening agent, a surface active agent, a plasticizer, a developing accelerator, a color coupler and a fluorescent brightening agent, by conventional means.
  • the photographic emulsion was applied to a cellulose triacetate film and dried to provide a photographic lightsensitive film.
  • Table 8 is shown the sensitizing ratio in the specific absorption wave length region of the silver halide when the sensitizing dye shown in the table was incorporated in the silver halide emulson containing silver halide crystals having a mean grain size of 0.07 micron. Also, in Table 9 are shown the sensitizing ratios when the sensitizing dyes 3, 11 and 22 were added to silver halide emulsions containing silver halide crystals having different mean grain sizes, respectively.
  • control sensitizing dyes used in the above table are as follows:
  • a negative silver halide photographic emulsion comprising a silver halide light-sensitive emulsion containing silver halide crystals having a mean grain size of smaller than 0.18 micron or at least 95% of which have grain sizes of smaller than 0.2 micron in diameter and having incorporated therein from 1 to mg. per kg. of emulsion, at least one of the sensitizing dyes represented by the following Formulae I, II, III, IV and V:
  • V and V or said W and W may form a benzene ring; with the proviso that when Z and Z' are each an oxygen atom, all of V, V W and W are a hydrogen atom or at least one of them is a phenyl group or a carboxyl group; with the further proviso that when Z and Z are N-R or NR all of V, V W, and W are a hydrogen atom or at least one of them is a halogen atom, and alkyl group having from 1 to 4 carbon atoms, a carboxyl group, an alkoxy group, a hydroxyl group, an acetyl group, a benzoyl group, an alkoxycarbonyl group, a nitrile group, a carbamyol group, a sulfamoyl group, an alkylsulfamoyl group, an acetylamino group, an alkylamino group, a trifluor
  • R and R each represents an alkyl group having from 1 to 4 carbon atoms or a substituted lower alkyl group and R and R which may be bonded to each other through a polymethylene chain, each represents an alkyl group having from 1 to 4 carbon atoms, an aryl group or an allyl group; all of V V W and W are a hydrogen atom or at least one of them is an alkyl group having from 1 to 4 carbon atoms, an alkoxyl group, a hydroxyl group, a phenyl group, or a halogen atom; wherein V and V or W and W may form a benzene ring; wherein R and R each represents an alkyl group having from 1 to 4 carbon atoms or a substituted lower alkyl group; wherein L represents CH, CH or CR11, wherein R represents a lower alkyl group, an alkoxyl group, a hydroxyl group, or a halogen atom; wherein two of said
  • R17 (IV) wherein 2;; represents an atomic group necessary to complete a S-membered or 6-membered heterocyclic ring; Q represents an atomic group necessary to complete a ketomethylene heterocyclic ring;
  • R represents an alkyl group having from 1 to 4 carbon atoms, a substituted lower alkyl group, or an allyl group;
  • L represents CH or C-R wherein R represents a substituted lower alkyl group or a substituted aryl group; wherein said R may be bonded to L through a polymethylene chain, wherein L represents the L nearest to the heteroyclic ring containing Z and m; is 1 or 2;
  • Q represents an oxygen atom, sulfur atom, or N-R Z and Z each represents an atomic group necessary to complete a S-membered or 6-membered heterocyclic ring
  • R R and R each represents a lower alkyl group or a substituted lower alkyl group
  • L L and L each represents CH or C-R22, wherein R represents a lower alkyl group, an alkoxyl group, an aryl group or a substituted aryl group
  • R represents an alkyl group having from 1 to 4 carbon atoms, a substituted lower alkyl group, an aryl group, or an allyl group
  • m is 0 or 1
  • X represents an anion; and wherein said R and L or said R and R may be bonded to each other through a polymethylene chain.
  • ketomethyleno heterocyclic ring 19 completed by Q is a rhodanine nuclei, a 2-thio-2,4(3,5)- oxazoledione nuclei, a 2-thioxydantoin nuclei, a 5-pyrazolone nuclei, a 4-thiazolidone nuclei, a 2-amino-4(5)- thiazole nuclei, a 2-alkylmercapto-4(S)-thiazole nuclei, or a barbituric acid nuclei.

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  • Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • General Physics & Mathematics (AREA)
  • Silver Salt Photography Or Processing Solution Therefor (AREA)
  • Non-Silver Salt Photosensitive Materials And Non-Silver Salt Photography (AREA)
  • Plural Heterocyclic Compounds (AREA)
  • Heterocyclic Carbon Compounds Containing A Hetero Ring Having Nitrogen And Oxygen As The Only Ring Hetero Atoms (AREA)
US38485A 1969-05-17 1970-05-18 Spectrally sensitized negative emulsion containing silver halide grains of less than 0.18 micron Expired - Lifetime US3706570A (en)

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JP44038248A JPS4931895B1 (enrdf_load_stackoverflow) 1969-05-17 1969-05-17

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JP (1) JPS4931895B1 (enrdf_load_stackoverflow)
BE (1) BE750499A (enrdf_load_stackoverflow)
CA (1) CA960899A (enrdf_load_stackoverflow)
DE (1) DE2024340A1 (enrdf_load_stackoverflow)
FR (1) FR2047812A5 (enrdf_load_stackoverflow)
GB (5) GB1317139A (enrdf_load_stackoverflow)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3867146A (en) * 1970-12-14 1975-02-18 Fuji Photo Film Co Ltd Holographic reproduction using carbocyanine dye sensitized, fine-grain silver halide emulsions and neon-helium lasers
US3890155A (en) * 1972-04-12 1975-06-17 Fuji Photo Film Co Ltd Radiation-sensitized fine-grained silver halide photographic sensitive material
US3988513A (en) * 1970-07-06 1976-10-26 Fuji Photo Film Co., Ltd. Silver halide emulsions for recording electron rays
US4657846A (en) * 1983-12-22 1987-04-14 Fuji Photo Film Co., Ltd. Silver halide photographic printing paper
US5183733A (en) * 1990-06-29 1993-02-02 Fuji Photo Film Co., Ltd. Silver halide photographic materials
US5238779A (en) * 1991-07-25 1993-08-24 Eastman Kodak Company Nucleated high contrast photographic elements containing low-stain sensitizing dyes
USH1336H (en) 1988-01-27 1994-07-05 Fuji Photo Film Co., Ltd. Silver halide photographic material
US5514533A (en) * 1992-08-27 1996-05-07 Fuji Photo Film Co., Ltd. Silver halide photographic photosensitive materials and a method for their processing
US5665328A (en) * 1988-05-02 1997-09-09 Phanos Technologies, Inc. Compounds, compositions and methods for binding bio-affecting substances to surface membranes of bio-particles
US6054259A (en) * 1997-03-18 2000-04-25 Fuji Photo Film Co., Ltd. Silver halide photographic material

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5062425A (enrdf_load_stackoverflow) * 1973-10-02 1975-05-28
JPS50137298U (enrdf_load_stackoverflow) * 1974-04-30 1975-11-12
JPS61173264U (enrdf_load_stackoverflow) * 1985-04-17 1986-10-28
US4889410A (en) * 1988-09-06 1989-12-26 Eastman Kodak Company Magenta filters
GB8925677D0 (en) * 1989-11-14 1990-01-04 Ilford Ltd Colour holograms

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3988513A (en) * 1970-07-06 1976-10-26 Fuji Photo Film Co., Ltd. Silver halide emulsions for recording electron rays
US3867146A (en) * 1970-12-14 1975-02-18 Fuji Photo Film Co Ltd Holographic reproduction using carbocyanine dye sensitized, fine-grain silver halide emulsions and neon-helium lasers
US3890155A (en) * 1972-04-12 1975-06-17 Fuji Photo Film Co Ltd Radiation-sensitized fine-grained silver halide photographic sensitive material
US4657846A (en) * 1983-12-22 1987-04-14 Fuji Photo Film Co., Ltd. Silver halide photographic printing paper
USH1336H (en) 1988-01-27 1994-07-05 Fuji Photo Film Co., Ltd. Silver halide photographic material
US5665328A (en) * 1988-05-02 1997-09-09 Phanos Technologies, Inc. Compounds, compositions and methods for binding bio-affecting substances to surface membranes of bio-particles
US5183733A (en) * 1990-06-29 1993-02-02 Fuji Photo Film Co., Ltd. Silver halide photographic materials
US5238779A (en) * 1991-07-25 1993-08-24 Eastman Kodak Company Nucleated high contrast photographic elements containing low-stain sensitizing dyes
US5514533A (en) * 1992-08-27 1996-05-07 Fuji Photo Film Co., Ltd. Silver halide photographic photosensitive materials and a method for their processing
US6054259A (en) * 1997-03-18 2000-04-25 Fuji Photo Film Co., Ltd. Silver halide photographic material

Also Published As

Publication number Publication date
BE750499A (fr) 1970-10-16
FR2047812A5 (enrdf_load_stackoverflow) 1971-03-12
CA960899A (en) 1975-01-14
GB1316493A (en) 1973-05-09
GB1317139A (en) 1973-05-16
GB1317140A (en) 1973-05-16
GB1317138A (en) 1973-05-16
DE2024340A1 (de) 1970-12-10
GB1317709A (en) 1973-05-23
JPS4931895B1 (enrdf_load_stackoverflow) 1974-08-26

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